Passenger-side air bag apparatus

ABSTRACT

An air bag module  4  is capable of passing through a glove box opening portion  1 B of an instrument panel  1.  An opening portion  4 B of a module case  4 A faces the inner surface of an air bag lid  3  molded in one piece with a top wall part 1C of the instrument panel  1.  The lower portion of the module case  4 A is fixed detachably to a steering hanger beam  5  via a lower portion tightening means  6  capable of operating via the glove box opening portion  1 B. The front of the upper portion of the module case  4 A is locked on and capable of engaging and removing with respect to the top wall part  1 C of the instrument panel  1  by a front locking means  7  capable of operating via the glove box opening portion  1 B. The rear of the upper portion of the module case  4 A is fixed detachably to the top wall part  1 C via a rear tightening means  8  capable of operating via the glove box opening portion  1 B.

FIELD OF THE INVENTION

[0001] The present invention relates to a passenger-side air bag apparatus, particularly, relates to a passenger-side air bag apparatus wherein an air bag module is placed within an instrument panel installed forward of a passenger seat and the air bag module can be easily attached and removed.

BACKGROUND OF THE INVENTION

[0002] A passenger-side air bag apparatus of a vehicle has an air bag module which houses an inflator and an air bag in a module case. The air bag module is supported by a structural member such as a steering hanger beam across an instrument panel and placed within the instrument panel installed forward of a passenger seat. An air bag lid is configured to be broken and open by inflation of the air bag. The air bag lid is mounted on the opening portion of the module case to cover the air bag in the module case, or molded in one piece on the top wall of the instrument panel installed forward of the passenger seat in advance.

[0003] The air bag module has the air bag lid mounted on the opening portion of the module case and the air bag module is inserted from above into an opening for mounting on the top wall of the instrument panel installed forward of the passenger seat. The lower portion of the module case is fixed detachably via the tightening means on the structural member such as a steering hanger beam. A tightening means includes a bracket, a stud bolt, a nut and the like. The edge of the air bag lid on the top end of the module case is locked on the periphery of the opening for mounting.

[0004] Another case will now be described in which the air bag lid is molded in one piece on the top wall of the instrument panel. In a state in which the opening portion of the module case is opposed to the inner surface of the air bag lid, the fore-and-aft part in the vicinity of the opening portion is fixed in advance detachably via the tightening means on the inner surface of the instrument panel. After the instrument panel is mounted on a car body, the lower portion of the module case is fixed detachably via the tightening means on the structural member such as a steering hanger beam.

[0005] There is a problem about the passenger-side air bag apparatus having the air bag module with the air bag lid. Specifically speaking, the airbag lid on the top end of the module case inserted into the opening for mounting on the top wall of the instrument panel is exposed at the outer surface of the instrument panel, therefore, togetherness of the instrument panel is impaired and the instrument panel is defiled.

[0006] The passenger-side air bag apparatus, which has the air bag lid molded in one piece on the top wall of the instrument panel in advance, is free from the above-described problem. However, There is another problem about this type of passenger-side air bag apparatus. Specifically speaking, when the air bag module is attached to and removed from the instrument panel to perform check or maintenance, the attaching and removing operation needs a multitude of man-hours. Front and rear tightening means fix the front and rear of the upper portion of the module case to the inner surface of the instrument panel. When the air bag module of this type of passenger-side air bag apparatus is attached to and removed from the instrument panel, the front and rear tightening means are to be attached and removed via such as an opening portion for a glove box of the instrument panel. In the state in which the instrument panel is mounted on a car body in practical, various structures such as a steering hanger beam, a dashboard and the like interfere with the operation. Therefore, the front tightening means of the upper portion of the module case cannot be attached and removed in practical. As a result, to attach and remove the air bag module, the instrument panel must be removed from the car body temporarily and a multitude of man-hours is needed.

[0007] Therefore, an object of the present invention is to provide a passenger-side air bag apparatus whose the air bag module can be easily attached and removed without defiling an instrument panel and without attaching and removing the instrument panel.

SUMMARY OF THE INVENTION

[0008] To achieve the above-mentioned object, a passenger-side air bag apparatus according to the present invention comprising:

[0009] an air bag lid molded in one piece with a top wall part of an instrument panel of the forward part of a passenger seat in a vehicle; and

[0010] an air bag module capable of passing through a glove box opening portion formed on a side wall part of said instrument panel of the forward part of a passenger seat;

[0011] wherein said air bag module is placed within said instrument panel in a state in which an opening portion of the top end of an module case housing an inflator and an air bag faces the inner surface of said air bag lid, the lower portion of said module case is fixed detachably to a structural member laid across said instrument panel via a lower portion tightening means provided being capable of operating via said glove box opening portion, and the upper portion of said module case is locked on and capable of engaging and removing with respect to said top wall part of said instrument panel via an upper locking means provided being capable of operating via said glove box opening portion.

[0012] The air bag module of a passenger-side air bag apparatus according to the present invention is taken out to the outside of the instrument panel to perform check or maintenance. First, a tool such as an impact wrench releases the lower portion tightening means. Next, the lower portion of the module case is removed from the structural member by manual work via the glove box opening portion. Subsequently, the module case is moved in a predetermined direction so that the upper locking means is released and the upper portion of the module case is removed from the top wall part of the instrument panel. The whole of the air bag module is then taken out from the glove box opening portion to the outside of the instrument panel. After the check and maintenance for the air bag module is performed, a reverse procedure is carried out for the air bag module. The upper portion of the module case is locked on the top wall part of the instrument panel by the upper locking means. The lower portion of the module case is fixed to a support member via the lower portion tightening means.

[0013] In regard to a passenger-side air bag apparatus according to the present invention, it is preferable that said upper locking means comprises a front locking means for locking the front of the upper portion of said module case and a rear locking means for locking the rear of the upper portion of said module case. The air bag breaks the air bag lid and then the air bag is inflated and developed toward the passenger seat of the rear part of the car body. The front and rear locking means prevent effectively the module case from moving to tilt in a fore-and-aft direction due to reaction of inflating and developing of the air bag.

[0014] In regard to a passenger-side air bag apparatus according to the present invention, it is preferable that said upper locking means comprises a front locking means for locking the front of the upper portion of said module case and the rear of the upper portion of said module case is fixed detachably to said top wall part of said instrument panel via a rear tightening means provided being capable of operating via said glove box opening portion. The air bag breaks the air bag lid and then the air bag is inflated and developed toward the passenger seat of the rear part of the car body. The front locking means and the rear tightening means prevent effectively still further the module case from moving to tilt in a fore-and-aft direction due to reaction of inflating and developing of the air bag.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is a perspective view showing appearance of an instrument panel of a vehicle in which an air bag module of a passenger-side air bag apparatus according to an embodiment is placed.

[0016]FIG. 2 is a sectional view taken along a line II-II in FIG. 1 showing installation structure of an air bag module of a passenger-side air bag apparatus according to an embodiment.

[0017]FIG. 3 is a sectional view corresponding to FIG. 2 showing attaching and removing operation of an air bag module of a passenger-side air bag apparatus according to an embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] An embodiment of a passenger-side air bag apparatus according to the present invention will now be described by referring to drawings. FIG. 1 is a perspective view showing appearance of an instrument panel of a vehicle in which an air bag module of a passenger-side air bag apparatus according to an embodiment is placed. FIG. 2 is a sectional view taken along a line II-II in FIG. 1 showing installation structure of an air bag module of a passenger-side air bag apparatus according to an embodiment.

[0019] As shown in FIGS. 1 and 2, a passenger-side air bag apparatus according to an embodiment is applied to an instrument panel 1 of a vehicle, and the instrument panel 1 has an opening portion 1B for a glove box (hereafter referred to as the glove box opening portion 1B) formed on a lower portion of a side wall part 1A of the forward part of a passenger seat. The glove box opening portion 1B has for a glove box 2 fitted therein being capable of opening and closing and mounted detachably. A top wall part 1C of the instrument panel 1 lies in the upper portion of the glove box 2. An air bag lid 3 of a passenger-side air bag apparatus according to an embodiment is molded in one piece with the top wall part 1C.

[0020] The air bag lid 3 is, as shown in FIG. 2, partitioned from the top wall part 1C by front and rear channels for hinge 3A, 3A (hereafter referred to as the hinge channels) and right and left channels for fracture 3B, 3B (hereafter referred to as the fracture channels) (see FIG. 1). The front and rear hinge channels 3A, 3A are formed on an inner surface of the top wall part 1C in a lateral direction of a vehicle body. The right and left fracture channels 3B, 3B are formed on the inner surface of the top wall part 1C in a fore-and-aft direction of a vehicle body. The midsection in a fore-and-aft direction of the inner surface of the air bag lid 3 has a channel for fracture 3C (hereafter referred to as the fracture channel) formed in parallel with the hinge channels 3A, 3A. An air bag of a passenger-side air bag apparatus according to an embodiment inflates and the fracture channels 3B, 3C of the air bag lid 3 are broken. The air bag lid 3 then rotates with the hinge channels 3A, 3A as supports toward the upper portion of the top wall part 1C in a fore-and-aft direction and the air bag lid 3 is opened.

[0021] An air bag module 4 of a passenger-side air bag apparatus according to an embodiment is set in sizes capable of passing through the glove box opening portion 1B of the instrument panel 1. A canaliculate module case 4A houses an inflator and the air bag (not shown). The air bag module 4 is placed within the instrument panel 1 in a state in which an opening portion 4B of the top end of the module case 4A faces the inner surface of the air bag lid 3.

[0022] The inflator is housed within a lower portion of the module case 4A. The inflator is ignited by an ignition signal from an acceleration sensor (not shown) and generates a high-pressure nitrogen gas. The air bag is housed in a predetermined shape in a folded state above the inflator. The high-pressure nitrogen gas generated by the inflator is blown into the air bag and then the air bag is inflated and developed.

[0023] The lower portion of the module case 4A of a passenger-side air bag apparatus according to an embodiment is fixed detachably to a steering hanger beam 5 via a lower portion tightening means 6. The steering hanger beam 5 is laid across the instrument panel 1 as a structural member. The lower portion tightening means 6 is provided being capable of operating via the glove box opening portion 1B. The lower portion tightening means 6 has a mount bracket 6A, a stud bolt 6B, a through hole 6C, a tightening bracket 6D and a nut 6E. The mount bracket 6A is welded on the rear of the steering hanger beam 5, which faces the glove box opening portion 1B. A base part of the stud bolt 6B is fixed on the mount bracket 6A and a tip part of the stud bolt 6B jets toward the glove box opening portion 1B. The through hole 6C for inserting the stud bolt 6B is formed on a lower portion of the tightening bracket 6D. The upper portion of the tightening bracket 6D is welded on the lower portion of the module case 4A. The nut 6E is screwed to the tip part of the stud bolt 6B piercing through the through hole 6C of the tightening bracket 6D.

[0024] The upper portion of the module case 4A is locked on and capable of engaging and removing with respect to the top wall part 1C of the instrument panel 1 via an upper locking means.

[0025] The upper locking means is provided being capable of operating via the glove box opening portion 1B. Specifically speaking, the front of the upper portion of the module case 4A of a passenger-side air bag apparatus according to an embodiment is locked on and capable of engaging and removing with respect to the top wall part 1C of a forward part of the air bag lid 3 via a front locking means 7. The front locking means 7 is provided being capable of operating via the glove box opening portion 1B. The front locking means 7 has an engaging pin 7A, a bushing 7B, a locking hole 7C and a locking bracket 7D. The engaging pin 7A is projected toward the front from the front of the upper portion of the module case 4A. The tip of the engaging pin 7A is covered with the bushing 7B for absorbing vibration. The locking hole 7C for inserting the bushing 7B is formed on a lower portion of the L-shaped cross-section locking bracket 7D. The upper portion of the locking bracket 7D is fixed on the inner surface of the top wall part 1C of the forward part of the air bag lid 3. The lower portion of the locking bracket 7D with the locking hole 7C faces the front of the upper portion of the module case 4A. The module case 4A is pushed forwardly by the manual work via the glove box opening portion 1B and then the engaging pin 7A can easily be inserted into the locking hole 7C via the bushing 7B.

[0026] The rear of the upper portion of the module case 4A is fixed detachably to the top wall part 1C of the rear part of the air bag lid 3 via a rear tightening means 8. The rear tightening means 8 is provided being capable of operating via the glove box opening portion 1B. The rear tightening means 8 has a stud bolt 8A, a through hole 8B, a tightening bracket 8C and a nut 8D. The stud bolt 8A downward is projected downward from the inner surface of the top wall part 1C of the rear part of the air bag lid 3. The through hole 8B for inserting the stud bolt 8A is formed on the upper portion of the L-shaped cross-section tightening bracket 8C. A lower portion of the tightening bracket 8C is welded on the rear of the upper portion of the module case 4A. The nut 8D is screwed to the lower end of the stud bolt 8A piercing through the through hole 8B of the tightening bracket 8C. The nut 8D is placed in a position wherein the nut 8D can be attached and removed easily by a tool such as an impact wrench inserted from the glove box opening portion 1B.

[0027] The operation will now be described wherein the air bag module 4 of the above-mentioned a passenger-side air bag apparatus according to an embodiment is taken out to the outside of the instrument panel 1 to perform check or maintenance. First, the glove box 2 placed forward of the passenger seat is opened, or the glove box 2 is removed and the glove box opening portion 1B of the instrument panel 1 is opened widely. A tool such as an impact wrench is inserted from the glove box opening portion 1B and the nut 6E is removed from the stud bolt 6B of the lower portion tightening means 6, at the same time the nut 8D is removed from the stud bolt 8A of the rear tightening means 8.

[0028] The lower portion of the module case 4A is lowered by manual work via the glove box opening portion 1B and the tightening bracket 8C is pulled out of the stud bolt 8A of the rear tightening means 8. The upper portion of the module case 4A is moved to tilt in a rear direction, at the same time the engaging pin 7A is pulled out of the locking hole 7C of locking bracket 7D with the bushing 7B. Subsequently, the lower portion of the module case 4A is pulled frontward and the tightening bracket 6D is pulled out of the stud bolt 6B of the lower portion tightening means 6. The whole of the air bag module 4 is taken out from the glove box opening portion 1B to the outside of the instrument panel 1 while the attitude of the air bag module 4 is changed as appropriate.

[0029] After the check and maintenance for the air bag module 4 is performed, a reverse procedure is carried out for the air bag module 4. The front of the upper portion of the module case 4A is first locked on the top wall part 1C of the forward part of the air bag lid 3 of the instrument panel 1 by the front locking means 7. Next, the rear of the upper portion of the module case 4A is fixed to the top wall part 1C of the rear part of the air bag lid 3 of the instrument panel 1 via a rear tightening means 8. The lower portion of the module case 4A is fixed to the steering hanger beam 5 via the lower portion tightening means 6.

[0030] In the state in which the air bag module 4 is fixed in this way, the engaging pin 7A of the front locking means 7 projected from the module case 4A is locked into the locking hole 7C of the locking bracket 7D via the bushing 7B for absorbing vibration. As a result of this, in case the module case 4A is vibrated by vehicle vibration, the vibration is absorbed and damped by the bushing 7B, therefore annoying vibration noise is prevented.

[0031] The air bag module 4 of a passenger-side air bag apparatus according to an embodiment is placed within the instrument panel 1. The inflator housed within the module case 4A is ignited by an ignition signal from an acceleration sensor (not shown) and generates a high-pressure nitrogen gas. The air bag housed within the module case 4A is inflated by the high-pressure nitrogen gas to break the air bag lid 3 and then inflated and developed from the air bag lid 3, which is opened in a fore-and-aft direction, toward the passenger seat of the rear part of the car body. At this time, reaction is applied to the module case 4A by inflating and developing of the air bag downward and forward with respect to the car body. However, in regard to a passenger-side air bag apparatus according to an embodiment, the lower portion of the module case 4A is fixed to the steering hanger beam 5 via the lower portion tightening means 6. The front of the upper portion of the module case 4A is locked on the top wall part 1C of the instrument panel 1 by the front locking means 7.

[0032] The rear of the upper portion of the module case 4A is fixed to the top wall part 1C via the rear tightening means 8. Therefore, the module case 4A can inflate and develop the air bag toward the passenger seat with reliability while an intended attitude of the module case 4A is maintained.

[0033] In regard to a passenger-side air bag apparatus according to the present invention, the upper locking means may include the above-mentioned front locking means 7 according to an embodiment and an extra rear locking means for locking the rear of the upper portion of the module case 4A. In this case, the rear tightening means 8 according to an embodiment can be simply diverted for the rear locking means. Specifically speaking, the nut 8D of the rear tightening means 8 is removed and the tip of the stud bolt 8A is covered with a bushing. The stud bolt BA may be replaced with an engaging pin.

[0034] In regard to a passenger-side air bag apparatus according to the present invention, the upper locking means may include a left locking means for locking the left of the upper portion of a module case and a right locking means for locking the right of the upper portion of the module case. The left locking means has, for example, an engaging pin, a bushing, a notch channel and a locking bracket. The engaging pin is projected toward the left from the left of the upper portion of the module case 4A according to an embodiment. The tip of the engaging pin is covered with the bushing. The notch channel in the shape of an L or the like for locking the bushing is formed on a lower portion of the L-shaped cross-section locking bracket. The upper portion of the locking bracket is fixed to the top wall part 1C of the left of the air bag lid 3. The right locking means may be symmetrical about the left locking means laterally.

[0035] In regard to a passenger-side air bag apparatus according to the present invention, an air bag lid molded in one piece with a top wall part of an instrument panel. Therefore, the instrument panel is not defiled. Further, an air bag module capable of passing through a glove box opening portion. A lower portion tightening means fixing the lower portion of said module case to a structural member is capable of attaching and removing from said glove box opening portion. An upper locking means locking the upper portion of said module case to said top wall part of said instrument panel is capable of engaging and removing with respect to said glove box opening portion. Therefore, the air bag module can be easily attached and removed without attaching and removing the instrument panel.

[0036] In regard to a passenger-side air bag apparatus according to the present invention, it is preferable that said upper locking means comprises a front locking means for locking the front of the upper portion of said module case and a rear locking means for locking the rear of the upper portion of said module case. The air bag breaks the air bag lid and then the air bag is inflated and developed toward the passenger seat of the rear part of the car body. The front and rear locking means prevent effectively the module case from moving to tilt in a fore-and-aft direction due to reaction of inflating and developing of the air bag. Therefore, the air bag module can be easily attached and removed, and the module case can inflate and develop the air bag toward the rear part of the car body with reliability.

[0037] In regard to a passenger-side air bag apparatus according to the present invention, it is preferable that said upper locking means comprises a front locking means for locking the front of the upper portion of said module case and the rear of the upper portion of said module case is fixed detachably to said top wall part of said instrument panel via a rear tightening means provided being capable of operating via said glove box opening portion. The air bag breaks the air bag lid and then the air bag is inflated and developed toward the passenger seat of the rear part of the car body. The front locking means and the rear tightening means prevent effectively still further the module case from moving to tilt in a fore-and-aft direction due to reaction of inflating and developing of the air bag. Therefore, the air bag module can be easily attached and removed, and the module case can inflate and develop the air bag toward the rear part of the car body with added reliability. 

What is claimed is:
 1. A passenger-side air bag apparatus comprising: an air bag lid molded in one piece with a top wall part of an instrument panel of the forward part of a passenger seat in a vehicle; and an air bag module capable of passing through a glove box opening portion formed on a side wall part of said instrument panel of the forward part of a passenger seat; wherein said air bag module is placed within said instrument panel in a state in which an opening portion of the top end of an module case housing an inflator and an air bag faces the inner surface of said air bag lid, the lower portion of said module case is fixed detachably to a structural member laid across said instrument panel via a lower portion tightening means provided being capable of operating via said glove box opening portion, and the upper portion of said module case is locked on and capable of engaging and removing with respect to said top wall part of said instrument panel via an upper locking means provided being capable of operating via said glove box opening portion.
 2. A passenger-side air bag apparatus according to claim 1, wherein said upper locking means comprises a front locking means for locking the front of the upper portion of said module case and a rear locking means for locking the rear of the upper portion of said module case.
 3. A passenger-side air bag apparatus according to claim 1, wherein said upper locking means is composed of comprises a front locking means for locking the front of the upper portion of said module case and the rear of the upper portion of said module case is fixed detachably to said top wall part of said instrument panel via a rear tightening means provided being capable of operating via said glove box opening portion.
 4. A passenger-side air bag apparatus according to claim 1, wherein said upper locking means comprises a left locking means for locking the left of the upper portion of said module case and a right locking means for locking the right of the upper portion of said module case. 